1. Field of the Invention
The present invention relates, generally, to interactive broadcast systems including interactive television (ITV) systems and, in particular embodiments, to such systems and processes for managing interactive advertisements and programming in ITV systems.
2. Description of Related Art
The emerging technology of ITV holds a promise of allowing a television (TV) set to serve as a two-way information distribution mechanism. Proposed features ITV accommodate a variety of marketing, entertainment, and educational capabilities such as allowing a user to order an advertised product or service, compete against contestants in a game show, or request specialized information regarding a televised program. Typically, the interactive functionality is controlled by a “set-top” decoder box (“set-top box” or “STB”) which executes an interactive program written for the TV broadcast. The interactive functionality is often displayed upon the TV's screen and may include icons or menus to allow a user to make selections via the TV's remote control or a keyboard.
The program interactivity may be optional. Thus, a user who chooses not to interact or who does not have interactive functionality included with the user's TV should not suffer any degradation or interruption in program content. In order to provide this option to users, a transparent method of incorporating interactive content into the broadcast stream that carries the program is employed. In the present disclosure, “broadcast stream” refers to the broadcast signal, whether analog or digital, regardless of the method of transmission of that signal, i.e. by antenna, satellite, cable, or any other method of analog or digital signal transmission.
One method of transparently incorporating interactive content into the broadcast stream is the insertion of triggers into the broadcast stream for a particular program. The insertion of triggers into a broadcast stream is well known in the art. Program content in which such triggers have been inserted is sometimes referred to as enhanced program content or as an enhanced TV program or video signal.
Triggers may be used to alert a STB that interactive content is available. The trigger may contain information about available enhanced content as well as the location of the enhanced content. A trigger may also contain user-perceptible text that is displayed on the screen, for example, at the bottom of the screen, which may prompt the user to perform some action or choose amongst a plurality of options. Thus, a user with a TV that has interactive functionality may be prompted at the beginning of an enhanced TV program to choose between interactive and passive (non-interactive) viewing of the enhanced TV program.
If the user chooses passive viewing, any further triggers contained in the enhanced TV program may be ignored by the STB and the user will view the program in a conventional way. However, if the user chooses the interactive option, then further triggers embedded in the enhanced TV program at predetermined times in the enhanced TV program may cause the presentation of interactive content to the user.
Triggers may be inserted into the broadcast stream at various points along the broadcast path. FIG. 1 shows a typical broadcast path 200 for program content. Triggers may be inserted into the broadcast stream before broadcast of the content by the broadcast station 202. Thus, these triggers would be part of the broadcast stream received by cable head ends 204 and 206 and further distributed to homes 208 and 210 and their respective TVs 212 and 214. TVs 212 and 214 are provided with interactive functionality by their associated STBs 216 and 218, respectively.
However, triggers may also be inserted at cable head ends 204 and 206, either for the first time or in addition to, or in place of, triggers previously inserted before broadcast from broadcast station 202. Thus, triggers inserted at cable head end 204 may trigger content specifically targeted at homes for which it provides cable service, such as home 208, while triggers inserted at cable head end 206 may trigger content specifically targeted at homes for which it provides cable service, such as home 210. Thus, advertisements or other content may be targeted to specific regions or even specific neighborhoods. This allows for very specific targeted marketing techniques to be applied to the viewing public.
One common method for inserting data such as triggers into an analog video signal is the placement of that data into the unused lines of the video signal that make up the vertical blanking interval (VBI). Closed caption text data is a well known example of the placement of data in the VBI of the video signal. The closed caption text data is typically transmitted during line 21 of either the odd or even field of the video frame in a National Television Standards Committee (NTSC) format. Closed caption decoders strip the encoded text data from the video signal, decode the text data, and reformat the data for display, concurrent with the video data, on a TV screen. Such closed caption decoders process the text data separately from the video signal.
The Advanced Television Enhancement Forum (ATVEF) has defined protocols for Hypertext Markup Language (HTML)-based enhanced TV. These protocols allow the delivery of enhanced TV programs to STBs and other devices providing interactive functionality by various transmission means, including, but not limited to, analog, digital, cable, and satellite. For the NTSC format, ATVEF specifies the type of information that may be inserted into the VBI of the video signal and on which lines of the VBI that information may be inserted. ATVEF specifies line 21 of the VBI as the line for insertion of an “ATVEF trigger,” i.e. the information that the STB or other device with interactive functionality interprets to provide interactive features to the enhanced TV program. ATVEF-A triggers comprise a Universal Resource Locator (URL) which provides an Internet address from which interactive content may be downloaded, whereas ATVEF-B triggers themselves can contain interactive content.
While the use of triggers to download interactive content from remote sites, or provide interactive content themselves, is known in the art, any control over such interactivity has been limited to discrete periods of time such as program times or commercial breaks, but not both. Thus, efficiencies that could result from controlling and sharing the given time space, to the extent possible, could not be achieved. A need therefore exists to manage both interactive program content and interactive commercial content, and schedule and integrate interactive content from multiple sources that may or may not be known in advance, without interference.